排序方式: 共有6条查询结果,搜索用时 31 毫秒
1
1.
Annette Herz Sherif A. Hassan Esmat Hegazi Feeby N. Nasr Ali A. Youssef W. E. Khafagi Essam Agamy Mohieddine Ksantini Taieb Jardak Basilis E. Mazomenos Maria A. Konstantopoulou Laura Torres Fátima Gonçalves Albino Bento José A. Pereira 《Gesunde Pflanzen》2005,57(5):117-128
Zusammenfassung Traditionelle, extensiv bearbeitete Olivenhaine, aber auch moderne Intensiv-Plantagen mit künstlicher Bewässerung und hohem Einsatz von Düngern bzw. chemischen Pflanzenschutzmitteln kennzeichnen die derzeitigen verschiedenen Anbauformen der Olive im Mittelmeerraum. Schadlepidopteren wie die Olivenmotte (Prays oleae, Lep.: Yponomeutidae) und die Jasminmotte (Palpita unionalis, Lep.: Pyralidae) werden durch regelmässigen Insektizideinsatz bekämpft. Das von der EU geförderte internationale Forschungsprojekt TRIPHELIO zielte auf die Entwicklung insektizidfreier Alternativmethoden durch (1) die Optimierung der pheromongestützten Überwachung und Verwirrtechnik, (2) der Anwendung von Habitatmanagement-Strategien zur Förderung natürlicher Gegenspieler, und (3) dem Einsatz von Trichogramma-Schlupfwespen. Zusätzlich wurden Module für eine optimale Anwendung biotechnischer und biologischer Methoden bezüglich der Phänologie der Schadinsekten und möglicher Nebenwirkungen von Pestiziden erarbeitet. Die intensive Kooperation zwischen Wissenschaftlern und Praktikern aus mehreren Ländern Europas und Nordafrikas erlaubte den Entwurf möglicher Lösungsansätze für verschiedene Anbaubedingungen und klimatische Regionen des Mittelmeerraumes. Die wichtigsten Ergebnisse und Ausblicke für eine zukünftige praktische Umsetzung werden in dieser Veröffentlichung beschrieben. 相似文献
2.
Ahlem Zrig Jorge F. S. Ferreira Foued Hamouda Taieb Tounekti Samy Selim Soad Al Jaouni 《Arid Land Research and Management》2019,33(3):297-320
Salinity reduces plant biomass and may lead to death when severe. To cope with the negative effects of this stress, plant species present specific physiological or biochemical responses. In this work, we hypothesized that spraying salt-stressed thyme leaves with K+ and Ca2+ could mitigate the negative effects of salinity on plant growth and metabolism. To test this hypothesis, we grew thyme plants under salinity stress for two and four weeks before applying foliar sprays. Also, to test the effect of stress relief, treated plants were allowed two weeks of recovery after four weeks of salt stress. In general, after two and four weeks of salinity stress, the leaf fresh weight of thyme plants was reduced by 31 and 43%, respectively. Salinity also decreased the relative water content, water, and osmotic potentials and led to ion imbalances and nutrient deficiencies. Salinity altered concentration of some essential oils, but leaf antioxidant contents remained fairly stable, except for a significant increase for plants under NaCl?+?KCl two weeks after treatment. Our results indicated that stressed plants accumulated significantly more soluble sugars and amino acids in comparison with the control. Foliar sprays with KCl and CaCl2 reversed the negative effects of salinity on plant biomass and induced the accumulations of compatible solutes. Moreover, concentrations of some essential oils and gallic acid increased in sprayed plants, but these effects were dependent on the type and duration of the treatment. Overall, spraying leaves with K+ and Ca2+ was able to mitigate salinity stress in Thymus vulgaris even during the recovery period. 相似文献
3.
Pappu S Gunnell Y Akhilesh K Braucher R Taieb M Demory F Thouveny N 《Science (New York, N.Y.)》2011,331(6024):1596-1599
South Asia is rich in Lower Paleolithic Acheulian sites. These have been attributed to the Middle Pleistocene on the basis of a small number of dates, with a few older but disputed age estimates. Here, we report new ages from the excavated site of Attirampakkam, where paleomagnetic measurements and direct (26)Al/(10)Be burial dating of stone artifacts now position the earliest Acheulian levels as no younger than 1.07 million years ago (Ma), with a pooled average age of 1.51 ± 0.07 Ma. These results reveal that, during the Early Pleistocene, India was already occupied by hominins fully conversant with an Acheulian technology including handaxes and cleavers among other artifacts. This implies that a spread of bifacial technologies across Asia occurred earlier than previously accepted. 相似文献
4.
Virachola livia Klug 1834 (Lepidoptera: Lycaenidae) was detected for the first time in a cultivated pomegranate orchard in Tunisia in 2006 although it may have been causing damage for several years prior to this. During 2006, 5.2% of the total pomegranate fruit produced in Tunisia was infested by this pest. This invasive species was responsible for 52% of fruit rot at Zerkine locality (Gabès Governorate). Levels of V. livia infection were shown to vary among nine pomegranate varieties; the Klaii, Mezzi and Garoussi varieties were the most susceptible, whereas Gabsi, Jbeli, Andolsi, Tounsi, Zaghweni and Zehri were more tolerant to this lycaenidae. The authors consider that this is due to female preference. 相似文献
5.
We examined the effects of drought on the water relations, osmotic adjustment and xylem vulnerability to embolism of olive (Olea europaea L.) varieties, 'Meski' and 'Chemlali'. Two-year-old self-rooted cuttings growing in sand-filled pots in a greenhouse were subjected to water stress by withholding water for 60 days. Water relations and gas exchange measurements showed that 'Chemlali' was more drought resistant than 'Meski' and had a greater capacity for osmotic adjustment through solute accumulation. However, when water stress was acute, the effect of osmoregulation on leaf cell turgor was largely counteracted by xylem cavitation. Cavitation vulnerability curves showed that both varieties were highly resistant to embolism formation. The xylem water potential inducing 50% loss of stem conductivity approached -7 MPa in 'Meski' and only slightly less in 'Chemlali'. Although the difference between varieties in susceptibility to xylem embolism was small, it appears to account in large part for the difference between them in the ability to tolerate severe drought. 相似文献
6.
Nougayrède JP Homburg S Taieb F Boury M Brzuszkiewicz E Gottschalk G Buchrieser C Hacker J Dobrindt U Oswald E 《Science (New York, N.Y.)》2006,313(5788):848-851
Transient infection of eukaryotic cells with commensal and extraintestinal pathogenic Escherichia coli of phylogenetic group B2 blocks mitosis and induces megalocytosis. This trait is linked to a widely spread genomic island that encodes giant modular nonribosomal peptide and polyketide synthases. Contact with E. coli expressing this gene cluster causes DNA double-strand breaks and activation of the DNA damage checkpoint pathway, leading to cell cycle arrest and eventually to cell death. Discovery of hybrid peptide-polyketide genotoxins in E. coli will change our view on pathogenesis and commensalism and open new biotechnological applications. 相似文献
1